With increasing industrial development, diverse electronic devices are used to achieve various purposes. An electronic device comprises a plurality of electronic components. Generally, different kinds of electronic components are operated by using different voltages.
As known, a power supply apparatus is essential for many electronic devices such as personal computers, industrial computers, servers, communication products or network products. Usually, the user may simply plug a power supply apparatus into an AC wall outlet commonly found in most homes or offices so as to receive an AC voltage. The power supply apparatus will convert the AC voltage into a regulated DC output voltage for powering the electronic device. The regulated DC output voltage is transmitted to the electronic device through a power cable. In addition, a power distribution unit (PDU) is used to distribute electric power among many different electronic devices. During the processes of supplying, converting and distributing electric power, plugs and sockets are important media for transmitting electric power. In other words, plugs and sockets are common components used in the power supply apparatus or the power distribution unit.
According to the internal safety regulation associated with the power distribution unit (PDU), the temperature of the socket of the power distribution unit should be lower than 70° C. With increasing integration of integrated circuits, the number of electronic components included in the power distribution unit is gradually increased and thus the power consumption of the power distribution unit is largely increased. Under this circumstance, the problem associated with heat-dissipation becomes more serious. During operation of the power distribution unit, the heat energy is generated from the electronic components of the power distribution unit and thus the temperature of the power distribution unit is increased. In other words, the temperature of the socket is increased. Although the electronic components of the power distribution unit may withstand 110˜150° C., the temperature of the socket should be lower than 70° C. in order to meet the safety regulation. That is, the design of the power distribution unit is restricted by the socket.
Moreover, the power distribution unit comprises plural power supply apparatuses for distributing electric power among many different electronic devices. These power supply apparatuses are connected with corresponding sockets through transmission cables. Since the transmission cables are metallic wires, the heat energy generated from the power supply apparatuses will be partially transmitted to the contact terminals between the transmission cables and the sockets. In addition, when a current is transmitted to the contact terminal of the socket through the metallic wire, heat energy is also generated from the contact impedance. Due to these heat generation sources, the temperature of the contact terminal of the socket is dramatically increased during the electricity transmission process. Since a great amount of heat energy is accumulated on the contact terminal of the socket, the socket is usually overheated and fails to meet the international safety regulation. If no addition heat-dissipating mechanism is used, the output current needs to be reduced in order to prevent from the overheated situation. The reduction of the output current, however, impairs the performance of the power distribution unit.
For solving the overheated problem of the power distribution unit, an active heat-dissipating module (e.g. a fan) is used for inhaling airflow inside the power distribution unit and exhausting the heat beside the socket out of the power distribution unit through the ventilation hole. Recently, the power distribution unit is gradually small-sized and slim. Since the active heat-dissipating module occupies much space of the power distribution unit, the use of the active heat-dissipating module is detrimental to minimization of the power distribution unit. Moreover, the use of the active heat-dissipating module will increase the fabricating cost of the power distribution unit. During operation of the fan, uncomfortable noise is usually generated. Since the operation of the fan consume a portion of electricity of the power distribution unit, the overall performance of the power distribution unit is deteriorated.
There is a need of providing a socket terminal heat-dissipating mechanism so as to obviate the drawbacks encountered from the prior art.